A dual antenna device includes a first antenna of a first polarization, a second antenna of a second polarization, and a conducting wall. The first antenna includes a grounding unit, a first substrate positioned on the grounding unit, a first radiating unit positioned on the first substrate, and a first feeding unit coupled to the first radiating unit. The conducting wall is coupled to the grounding unit and the first radiating unit, and forms a space above the grounding unit. The second antenna includes a second radiating unit and a second feeding unit coupled to the second radiating unit and placed through the space.